Fluorescent lamps (also known as gas discharge lamps) economically illuminate an area. Due to the unique operating characteristics of fluorescent lamps, the lamps must be powered by a ballast. Ballasts provide high ignition voltages for starting the lamps. For example, the ignition voltages supplied by preheat type ballasts are typically on the order of several hundred volts (e.g., 500 volts peak), while those provided by instant-start type ballasts may exceed 1000 volts peak. As a result of such high ignition voltages, arcing may occur during operation of ballasts. For example, an arc may form between a lamp holder contacts and a pin of the lamp when a lamp is being removed from the holder or inserted into the holder. According to ANSI/UL specifications, the duration an arc is present should be less than a specified time period. Thus, a need exists for a ballast having a detection circuit that readily detects an arc condition and that, in response to a detected arc condition, shuts down the ballast in order to eliminate the arc condition. However, during operation of an instant-start, or programme-start type ballast, there are high increases in ballast voltages and currents during normal ignition of lamp(s) which may appear as similar to an arc condition. To avoid shutting down the ballast during this normal operation, there is need for a ballast circuit that shuts down the ballast during an arc condition, but that does not shut down the ballast during an ignition period.